A union is taking a legal case on behalf of home care workers, saying they are paid less than half the minimum wage.

Seventeen home care workers employed across the London Borough of Haringey, backed by their union Unison, are taking a number of care companies and the council to court claiming widespread non-payment of the minimum wage.

The group, all but one of whom are women, are employed on controversial zero-hours contracts and care for elderly and disabled residents across the borough.

The women visit people in their own homes and in some cases provide 24-hour live-in care.

The case against care companies who took over a contract from Sevacare, centres on unpaid time spent travelling between people's houses.

Unison said on a typical day the women might be working away from home for 14 hours, but could receive payment for only half of them, leaving them earning as little as £3.85 an hour.

Care workers who provide live-in care can earn even less, getting as little as £3.27 an hour, well under half the legal minimum, said Unison.

General secretary Dave Prentis said: "Without the dedication of these committed and caring women, and thousands of others like them across the UK, our care system would collapse.

"The Government, local councils and the care companies all know that social care is in a dire state, that there's not enough money to pay for the care that's needed, and with everyone living longer the situation is going to get worse.

"The blame for the social care crisis must be laid at the Government's door. Ministers must get tougher with enforcing the law so firms aren't able to cheat their staff.

"More money must be put into care so that councils are not forced to tender contracts at a price they know decent care cannot be delivered. No wonder 15-minute care visits are now the norm, and there's widespread payment of illegal wages.

"Those paying the price for the Government's penny-pinching approach are the homecare workers - struggling to make ends meet on pitiful wages - and the people they care for. Their often complex medical needs simply cannot be catered for within the short time allocated by the care companies. Meanwhile the companies are coining it in."

Unison said it was biggest the union has ever taken involving home care workers.

Sevacare, which no longer has a contract with Haringey, insisted it paid over the minimum wage and disputed that women had worked 24 hours a day.

Workers were paid for an average of 10 hours day, equivalent to an hourly rate of £7.85, said the company, adding that its rates were at least in line with the national minimum wage.

Alistair Burt, who was the care and support minister until July, told the BBC the case concerned him.

"The law is not clear. All care workers should be valued, should be paid at least the minimum wage."

A spokesman for Haringey Council said: "Haringey ended its relationship with Sevacare in April after previously raising serious concerns with the Care Quality Commission.

"We contractually require providers to obey minimum wage law, including remuneration for travel time, and regularly seek information from providers on how much they pay their staff.

"We also have a robust whistle-blowing process and will promptly investigate any claims that staff are not being paid enough to meet minimum wage and travel time. We will impose appropriate sanctions if wrongdoing is found.

"Our rates allow for providers to pay both the national minimum wage and the national living wage, and we will be writing to them all to remind them of their Care Act obligations, stating clearly that no breaches will be tolerated."

A Business Department spokesman said: "Everyone entitled to the minimum wage or living wage should receive it - that is the law.

"Although we can't comment on individual cases or ongoing investigations, social care has been identified as a sector where people are more at risk of being underpaid and HMRC prioritises compliance in this area.

"We are clear that when employers do not comply with the law, they will be found out and punished, and we would encourage any worker who's concerned to contact Acas. Every complaint received is fully investigated by HMRC."